Ejemplo n.º 1
0
/**
    Purpose
    -------
    SSYEVD computes all eigenvalues and, optionally, eigenvectors of
    a real symmetric matrix A.  If eigenvectors are desired, it uses a
    divide and conquer algorithm.

    The divide and conquer algorithm makes very mild assumptions about
    floating point arithmetic. It will work on machines with a guard
    digit in add/subtract, or on those binary machines without guard
    digits which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or
    Cray-2. It could conceivably fail on hexadecimal or decimal machines
    without guard digits, but we know of none.

    Arguments
    ---------
    @param[in]
    jobz    magma_vec_t
      -     = MagmaNoVec:  Compute eigenvalues only;
      -     = MagmaVec:    Compute eigenvalues and eigenvectors.

    @param[in]
    uplo    magma_uplo_t
      -     = MagmaUpper:  Upper triangle of A is stored;
      -     = MagmaLower:  Lower triangle of A is stored.

    @param[in]
    n       INTEGER
            The order of the matrix A.  N >= 0.

    @param[in,out]
    A       REAL array, dimension (LDA, N)
            On entry, the symmetric matrix A.  If UPLO = MagmaUpper, the
            leading N-by-N upper triangular part of A contains the
            upper triangular part of the matrix A.  If UPLO = MagmaLower,
            the leading N-by-N lower triangular part of A contains
            the lower triangular part of the matrix A.
            On exit, if JOBZ = MagmaVec, then if INFO = 0, A contains the
            orthonormal eigenvectors of the matrix A.
            If JOBZ = MagmaNoVec, then on exit the lower triangle (if UPLO=MagmaLower)
            or the upper triangle (if UPLO=MagmaUpper) of A, including the
            diagonal, is destroyed.

    @param[in]
    lda     INTEGER
            The leading dimension of the array A.  LDA >= max(1,N).

    @param[out]
    w       REAL array, dimension (N)
            If INFO = 0, the eigenvalues in ascending order.

    @param[out]
    work    (workspace) REAL array, dimension (MAX(1,LWORK))
            On exit, if INFO = 0, WORK[0] returns the optimal LWORK.

    @param[in]
    lwork   INTEGER
            The length of the array WORK.
            If N <= 1,                      LWORK >= 1.
            If JOBZ = MagmaNoVec and N > 1, LWORK >= 2*N + N*NB.
            If JOBZ = MagmaVec   and N > 1, LWORK >= max( 2*N + N*NB, 1 + 6*N + 2*N**2 ).
            NB can be obtained through magma_get_ssytrd_nb(N).
    \n
            If LWORK = -1, then a workspace query is assumed; the routine
            only calculates the optimal sizes of the WORK and IWORK
            arrays, returns these values as the first entries of the WORK
            and IWORK arrays, and no error message related to LWORK or
            LIWORK is issued by XERBLA.

    @param[out]
    iwork   (workspace) INTEGER array, dimension (MAX(1,LIWORK))
            On exit, if INFO = 0, IWORK[0] returns the optimal LIWORK.

    @param[in]
    liwork  INTEGER
            The dimension of the array IWORK.
            If N <= 1,                      LIWORK >= 1.
            If JOBZ = MagmaNoVec and N > 1, LIWORK >= 1.
            If JOBZ = MagmaVec   and N > 1, LIWORK >= 3 + 5*N.
    \n
            If LIWORK = -1, then a workspace query is assumed; the
            routine only calculates the optimal sizes of the WORK and
            IWORK arrays, returns these values as the first entries of
            the WORK and IWORK arrays, and no error message related to
            LWORK or LIWORK is issued by XERBLA.

    @param[out]
    info    INTEGER
      -     = 0:  successful exit
      -     < 0:  if INFO = -i, the i-th argument had an illegal value
      -     > 0:  if INFO = i and JOBZ = MagmaNoVec, then the algorithm failed
                  to converge; i off-diagonal elements of an intermediate
                  tridiagonal form did not converge to zero;
                  if INFO = i and JOBZ = MagmaVec, then the algorithm failed
                  to compute an eigenvalue while working on the submatrix
                  lying in rows and columns INFO/(N+1) through
                  mod(INFO,N+1).

    Further Details
    ---------------
    Based on contributions by
       Jeff Rutter, Computer Science Division, University of California
       at Berkeley, USA

    Modified description of INFO. Sven, 16 Feb 05.

    @ingroup magma_ssyev_driver
    ********************************************************************/
extern "C" magma_int_t
magma_ssyevd(magma_vec_t jobz, magma_uplo_t uplo,
             magma_int_t n,
             float *A, magma_int_t lda,
             float *w,
             float *work, magma_int_t lwork,
             magma_int_t *iwork, magma_int_t liwork,
             magma_int_t *info)
{
    const char* uplo_ = lapack_uplo_const( uplo );
    const char* jobz_ = lapack_vec_const( jobz );
    magma_int_t ione = 1;
    magma_int_t izero = 0;
    float d_one = 1.;

    float d__1;

    float eps;
    magma_int_t inde;
    float anrm;
    float rmin, rmax;
    float sigma;
    magma_int_t iinfo, lwmin;
    magma_int_t lower;
    magma_int_t wantz;
    magma_int_t indwk2, llwrk2;
    magma_int_t iscale;
    float safmin;
    float bignum;
    magma_int_t indtau;
    magma_int_t indwrk, liwmin;
    magma_int_t llwork;
    float smlnum;
    magma_int_t lquery;

    float* dwork;

    wantz = (jobz == MagmaVec);
    lower = (uplo == MagmaLower);
    lquery = (lwork == -1 || liwork == -1);

    *info = 0;

    if (! (wantz || (jobz == MagmaNoVec))) {
        *info = -1;
    } else if (! (lower || (uplo == MagmaUpper))) {
        *info = -2;
    } else if (n < 0) {
        *info = -3;
    } else if (lda < max(1,n)) {
        *info = -5;
    }

    magma_int_t nb = magma_get_ssytrd_nb( n );
    if ( n <= 1 ) {
        lwmin  = 1;
        liwmin = 1;
    }
    else if ( wantz ) {
        lwmin  = max( 2*n + n*nb, 1 + 6*n + 2*n*n );
        liwmin = 3 + 5*n;
    }
    else {
        lwmin  = 2*n + n*nb;
        liwmin = 1;
    }
    // multiply by 1+eps to ensure length gets rounded up,
    // if it cannot be exactly represented in floating point.
    float one_eps = 1. + lapackf77_slamch("Epsilon");
    work[0]  = lwmin * one_eps;
    iwork[0] = liwmin;

    if ((lwork < lwmin) && !lquery) {
        *info = -8;
    } else if ((liwork < liwmin) && ! lquery) {
        *info = -10;
    }

    if (*info != 0) {
        magma_xerbla( __func__, -(*info) );
        return *info;
    }
    else if (lquery) {
        return *info;
    }

    /* Quick return if possible */
    if (n == 0) {
        return *info;
    }

    if (n == 1) {
        w[0] = A[0];
        if (wantz) {
            A[0] = 1.;
        }
        return *info;
    }
    
    /* Check if matrix is very small then just call LAPACK on CPU, no need for GPU */
    if (n <= 128) {
        #ifdef ENABLE_DEBUG
        printf("--------------------------------------------------------------\n");
        printf("  warning matrix too small N=%d NB=%d, calling lapack on CPU  \n", (int) n, (int) nb);
        printf("--------------------------------------------------------------\n");
        #endif
        lapackf77_ssyevd(jobz_, uplo_,
                         &n, A, &lda,
                         w, work, &lwork,
                         iwork, &liwork, info);
        return *info;
    }

    /* Get machine constants. */
    safmin = lapackf77_slamch("Safe minimum");
    eps    = lapackf77_slamch("Precision");
    smlnum = safmin / eps;
    bignum = 1. / smlnum;
    rmin = magma_ssqrt(smlnum);
    rmax = magma_ssqrt(bignum);

    /* Scale matrix to allowable range, if necessary. */
    anrm = lapackf77_slansy("M", uplo_, &n, A, &lda, work );
    iscale = 0;
    if (anrm > 0. && anrm < rmin) {
        iscale = 1;
        sigma = rmin / anrm;
    } else if (anrm > rmax) {
        iscale = 1;
        sigma = rmax / anrm;
    }
    if (iscale == 1) {
        lapackf77_slascl(uplo_, &izero, &izero, &d_one, &sigma, &n, &n, A,
                &lda, info);
    }

    /* Call SSYTRD to reduce symmetric matrix to tridiagonal form. */
    // ssytrd work: e (n) + tau (n) + llwork (n*nb)  ==>  2n + n*nb
    // sstedx work: e (n) + tau (n) + z (n*n) + llwrk2 (1 + 4*n + n^2)  ==>  1 + 6n + 2n^2
    inde   = 0;
    indtau = inde   + n;
    indwrk = indtau + n;
    indwk2 = indwrk + n*n;
    llwork = lwork - indwrk;
    llwrk2 = lwork - indwk2;



    magma_ssytrd(uplo, n, A, lda, w, &work[inde],
                 &work[indtau], &work[indwrk], llwork, &iinfo);


    /* For eigenvalues only, call SSTERF.  For eigenvectors, first call
       SSTEDC to generate the eigenvector matrix, WORK(INDWRK), of the
       tridiagonal matrix, then call SORMTR to multiply it to the Householder
       transformations represented as Householder vectors in A. */
    if (! wantz) {
        lapackf77_ssterf(&n, w, &work[inde], info);
    }
    else {


        if (MAGMA_SUCCESS != magma_smalloc( &dwork, 3*n*(n/2 + 1) )) {
            *info = MAGMA_ERR_DEVICE_ALLOC;
            return *info;
        }

        // TTT Possible bug for n < 128
        magma_sstedx(311, n, 0., 0., 0, 0, w, &work[inde],
                     &work[indwrk], n, &work[indwk2],
                     llwrk2, iwork, liwork, dwork, info);

        magma_free( dwork );


        magma_sormtr(MagmaLeft, uplo, MagmaNoTrans, n, n, A, lda, &work[indtau],
                     &work[indwrk], n, &work[indwk2], llwrk2, &iinfo);

        lapackf77_slacpy("A", &n, &n, &work[indwrk], &n, A, &lda);

    }

    /* If matrix was scaled, then rescale eigenvalues appropriately. */
    if (iscale == 1) {
        d__1 = 1. / sigma;
        blasf77_sscal(&n, &d__1, w, &ione);
    }

    work[0]  = lwmin * one_eps;  // round up
    iwork[0] = liwmin;

    return *info;
} /* magma_ssyevd */
Ejemplo n.º 2
0
/**
    Purpose
    -------
    SSYEVDX computes selected eigenvalues and, optionally, eigenvectors
    of a real symmetric matrix A. Eigenvalues and eigenvectors can
    be selected by specifying either a range of values or a range of
    indices for the desired eigenvalues.
    If eigenvectors are desired, it uses a divide and conquer algorithm.

    The divide and conquer algorithm makes very mild assumptions about
    floating point arithmetic. It will work on machines with a guard
    digit in add/subtract, or on those binary machines without guard
    digits which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or
    Cray-2. It could conceivably fail on hexadecimal or decimal machines
    without guard digits, but we know of none.

    Arguments
    ---------
    @param[in]
    jobz    magma_vec_t
      -     = MagmaNoVec:  Compute eigenvalues only;
      -     = MagmaVec:    Compute eigenvalues and eigenvectors.

    @param[in]
    range   magma_range_t
      -     = MagmaRangeAll: all eigenvalues will be found.
      -     = MagmaRangeV:   all eigenvalues in the half-open interval (VL,VU]
                   will be found.
      -     = MagmaRangeI:   the IL-th through IU-th eigenvalues will be found.

    @param[in]
    uplo    magma_uplo_t
      -     = MagmaUpper:  Upper triangle of A is stored;
      -     = MagmaLower:  Lower triangle of A is stored.

    @param[in]
    n       INTEGER
            The order of the matrix A.  N >= 0.

    @param[in,out]
    dA      REAL array on the GPU,
            dimension (LDDA, N).
            On entry, the symmetric matrix A.  If UPLO = MagmaUpper, the
            leading N-by-N upper triangular part of A contains the
            upper triangular part of the matrix A.  If UPLO = MagmaLower,
            the leading N-by-N lower triangular part of A contains
            the lower triangular part of the matrix A.
            On exit, if JOBZ = MagmaVec, then if INFO = 0, the first m columns
            of A contains the required
            orthonormal eigenvectors of the matrix A.
            If JOBZ = MagmaNoVec, then on exit the lower triangle (if UPLO=MagmaLower)
            or the upper triangle (if UPLO=MagmaUpper) of A, including the
            diagonal, is destroyed.

    @param[in]
    ldda    INTEGER
            The leading dimension of the array DA.  LDDA >= max(1,N).

    @param[in]
    vl      REAL
    @param[in]
    vu      REAL
            If RANGE=MagmaRangeV, the lower and upper bounds of the interval to
            be searched for eigenvalues. VL < VU.
            Not referenced if RANGE = MagmaRangeAll or MagmaRangeI.

    @param[in]
    il      INTEGER
    @param[in]
    iu      INTEGER
            If RANGE=MagmaRangeI, the indices (in ascending order) of the
            smallest and largest eigenvalues to be returned.
            1 <= IL <= IU <= N, if N > 0; IL = 1 and IU = 0 if N = 0.
            Not referenced if RANGE = MagmaRangeAll or MagmaRangeV.

    @param[out]
    m       INTEGER
            The total number of eigenvalues found.  0 <= M <= N.
            If RANGE = MagmaRangeAll, M = N, and if RANGE = MagmaRangeI, M = IU-IL+1.

    @param[out]
    w       REAL array, dimension (N)
            If INFO = 0, the required m eigenvalues in ascending order.

    @param
    wA      (workspace) REAL array, dimension (LDWA, N)

    @param[in]
    ldwa    INTEGER
            The leading dimension of the array wA.  LDWA >= max(1,N).

    @param[out]
    work    (workspace) REAL array, dimension (MAX(1,LWORK))
            On exit, if INFO = 0, WORK[0] returns the optimal LWORK.

    @param[in]
    lwork   INTEGER
            The length of the array WORK.
            If N <= 1,                      LWORK >= 1.
            If JOBZ = MagmaNoVec and N > 1, LWORK >= 2*N + N*NB.
            If JOBZ = MagmaVec   and N > 1, LWORK >= max( 2*N + N*NB, 1 + 6*N + 2*N**2 ).
            NB can be obtained through magma_get_ssytrd_nb(N).
    \n
            If LWORK = -1, then a workspace query is assumed; the routine
            only calculates the optimal sizes of the WORK and IWORK
            arrays, returns these values as the first entries of the WORK
            and IWORK arrays, and no error message related to LWORK or
            LIWORK is issued by XERBLA.

    @param[out]
    iwork   (workspace) INTEGER array, dimension (MAX(1,LIWORK))
            On exit, if INFO = 0, IWORK[0] returns the optimal LIWORK.

    @param[in]
    liwork  INTEGER
            The dimension of the array IWORK.
            If N <= 1,                      LIWORK >= 1.
            If JOBZ = MagmaNoVec and N > 1, LIWORK >= 1.
            If JOBZ = MagmaVec   and N > 1, LIWORK >= 3 + 5*N.
    \n
            If LIWORK = -1, then a workspace query is assumed; the
            routine only calculates the optimal sizes of the WORK and
            IWORK arrays, returns these values as the first entries of
            the WORK and IWORK arrays, and no error message related to
            LWORK or LIWORK is issued by XERBLA.

    @param[out]
    info    INTEGER
      -     = 0:  successful exit
      -     < 0:  if INFO = -i, the i-th argument had an illegal value
      -     > 0:  if INFO = i and JOBZ = MagmaNoVec, then the algorithm failed
                  to converge; i off-diagonal elements of an intermediate
                  tridiagonal form did not converge to zero;
                  if INFO = i and JOBZ = MagmaVec, then the algorithm failed
                  to compute an eigenvalue while working on the submatrix
                  lying in rows and columns INFO/(N+1) through
                  mod(INFO,N+1).

    Further Details
    ---------------
    Based on contributions by
       Jeff Rutter, Computer Science Division, University of California
       at Berkeley, USA

    Modified description of INFO. Sven, 16 Feb 05.

    @ingroup magma_ssyev_driver
    ********************************************************************/
extern "C" magma_int_t
magma_ssyevdx_gpu(magma_vec_t jobz, magma_range_t range, magma_uplo_t uplo,
                  magma_int_t n,
                  float *dA, magma_int_t ldda,
                  float vl, float vu, magma_int_t il, magma_int_t iu,
                  magma_int_t *m, float *w,
                  float *wA,  magma_int_t ldwa,
                  float *work, magma_int_t lwork,
                  magma_int_t *iwork, magma_int_t liwork,
                  magma_int_t *info)
{
    magma_int_t ione = 1;

    float d__1;

    float eps;
    magma_int_t inde;
    float anrm;
    float rmin, rmax;
    float sigma;
    magma_int_t iinfo, lwmin;
    magma_int_t lower;
    magma_int_t wantz;
    magma_int_t indwk2, llwrk2;
    magma_int_t iscale;
    float safmin;
    float bignum;
    magma_int_t indtau;
    magma_int_t indwrk, liwmin;
    magma_int_t llwork;
    float smlnum;
    magma_int_t lquery;
    magma_int_t alleig, valeig, indeig;

    float *dwork;
    magma_int_t lddc = ldda;

    wantz = (jobz == MagmaVec);
    lower = (uplo == MagmaLower);

    alleig = (range == MagmaRangeAll);
    valeig = (range == MagmaRangeV);
    indeig = (range == MagmaRangeI);

    lquery = (lwork == -1 || liwork == -1);

    *info = 0;
    if (! (wantz || (jobz == MagmaNoVec))) {
        *info = -1;
    } else if (! (alleig || valeig || indeig)) {
        *info = -2;
    } else if (! (lower || (uplo == MagmaUpper))) {
        *info = -3;
    } else if (n < 0) {
        *info = -4;
    } else if (ldda < max(1,n)) {
        *info = -6;
    } else if (ldwa < max(1,n)) {
        *info = -14;
    } else {
        if (valeig) {
            if (n > 0 && vu <= vl) {
                *info = -8;
            }
        } else if (indeig) {
            if (il < 1 || il > max(1,n)) {
                *info = -9;
            } else if (iu < min(n,il) || iu > n) {
                *info = -10;
            }
        }
    }

    magma_int_t nb = magma_get_ssytrd_nb( n );
    if ( n <= 1 ) {
        lwmin  = 1;
        liwmin = 1;
    }
    else if ( wantz ) {
        lwmin  = max( 2*n + n*nb, 1 + 6*n + 2*n*n );
        liwmin = 3 + 5*n;
    }
    else {
        lwmin  = 2*n + n*nb;
        liwmin = 1;
    }
    
    // multiply by 1+eps (in Double!) to ensure length gets rounded up,
    // if it cannot be exactly represented in floating point.
    real_Double_t one_eps = 1. + lapackf77_slamch("Epsilon");
    work[0]  = lwmin * one_eps;
    iwork[0] = liwmin;

    if ((lwork < lwmin) && !lquery) {
        *info = -16;
    } else if ((liwork < liwmin) && ! lquery) {
        *info = -18;
    }

    if (*info != 0) {
        magma_xerbla( __func__, -(*info) );
        return *info;
    }
    else if (lquery) {
        return *info;
    }

    /* Check if matrix is very small then just call LAPACK on CPU, no need for GPU */
    if (n <= 128) {
        #ifdef ENABLE_DEBUG
        printf("--------------------------------------------------------------\n");
        printf("  warning matrix too small N=%d NB=%d, calling lapack on CPU  \n", (int) n, (int) nb);
        printf("--------------------------------------------------------------\n");
        #endif
        const char* jobz_ = lapack_vec_const( jobz );
        const char* uplo_ = lapack_uplo_const( uplo );
        float *A;
        magma_smalloc_cpu( &A, n*n );
        magma_sgetmatrix(n, n, dA, ldda, A, n);
        lapackf77_ssyevd(jobz_, uplo_,
                         &n, A, &n,
                         w, work, &lwork,
                         iwork, &liwork, info);
        magma_ssetmatrix( n, n, A, n, dA, ldda);
        magma_free_cpu(A);
        return *info;
    }

    magma_queue_t stream;
    magma_queue_create( &stream );

    // n*lddc for ssytrd2_gpu
    // n for slansy
    magma_int_t ldwork = n*lddc;
    if ( wantz ) {
        // need 3n^2/2 for sstedx
        ldwork = max( ldwork, 3*n*(n/2 + 1));
    }
    if (MAGMA_SUCCESS != magma_smalloc( &dwork, ldwork )) {
        *info = MAGMA_ERR_DEVICE_ALLOC;
        return *info;
    }

    /* Get machine constants. */
    safmin = lapackf77_slamch("Safe minimum");
    eps    = lapackf77_slamch("Precision");
    smlnum = safmin / eps;
    bignum = 1. / smlnum;
    rmin = magma_ssqrt(smlnum);
    rmax = magma_ssqrt(bignum);

    /* Scale matrix to allowable range, if necessary. */
    anrm = magmablas_slansy(MagmaMaxNorm, uplo, n, dA, ldda, dwork);
    iscale = 0;
    sigma  = 1;
    if (anrm > 0. && anrm < rmin) {
        iscale = 1;
        sigma = rmin / anrm;
    } else if (anrm > rmax) {
        iscale = 1;
        sigma = rmax / anrm;
    }
    if (iscale == 1) {
        magmablas_slascl(uplo, 0, 0, 1., sigma, n, n, dA, ldda, info);
    }

    /* Call SSYTRD to reduce symmetric matrix to tridiagonal form. */
    // ssytrd work: e (n) + tau (n) + llwork (n*nb)  ==>  2n + n*nb
    // sstedx work: e (n) + tau (n) + z (n*n) + llwrk2 (1 + 4*n + n^2)  ==>  1 + 6n + 2n^2
    inde   = 0;
    indtau = inde   + n;
    indwrk = indtau + n;
    indwk2 = indwrk + n*n;
    llwork = lwork - indwrk;
    llwrk2 = lwork - indwk2;

    magma_timer_t time=0;
    timer_start( time );

#ifdef FAST_SYMV
    magma_ssytrd2_gpu(uplo, n, dA, ldda, w, &work[inde],
                      &work[indtau], wA, ldwa, &work[indwrk], llwork,
                      dwork, n*lddc, &iinfo);
#else
    magma_ssytrd_gpu(uplo, n, dA, ldda, w, &work[inde],
                     &work[indtau], wA, ldwa, &work[indwrk], llwork,
                     &iinfo);
#endif

    timer_stop( time );
    timer_printf( "time ssytrd = %6.2f\n", time );

    /* For eigenvalues only, call SSTERF.  For eigenvectors, first call
       SSTEDC to generate the eigenvector matrix, WORK(INDWRK), of the
       tridiagonal matrix, then call SORMTR to multiply it to the Householder
       transformations represented as Householder vectors in A. */

    if (! wantz) {
        lapackf77_ssterf(&n, w, &work[inde], info);

        magma_smove_eig(range, n, w, &il, &iu, vl, vu, m);
    }
    else {
        timer_start( time );

        magma_sstedx(range, n, vl, vu, il, iu, w, &work[inde],
                     &work[indwrk], n, &work[indwk2],
                     llwrk2, iwork, liwork, dwork, info);

        timer_stop( time );
        timer_printf( "time sstedx = %6.2f\n", time );
        timer_start( time );

        magma_smove_eig(range, n, w, &il, &iu, vl, vu, m);

        magma_ssetmatrix( n, *m, &work[indwrk + n* (il-1) ], n, dwork, lddc );

        magma_sormtr_gpu(MagmaLeft, uplo, MagmaNoTrans, n, *m, dA, ldda, &work[indtau],
                         dwork, lddc, wA, ldwa, &iinfo);

        magma_scopymatrix( n, *m, dwork, lddc, dA, ldda );

        timer_stop( time );
        timer_printf( "time sormtr + copy = %6.2f\n", time );
    }

    /* If matrix was scaled, then rescale eigenvalues appropriately. */
    if (iscale == 1) {
        d__1 = 1. / sigma;
        blasf77_sscal(&n, &d__1, w, &ione);
    }

    work[0]  = lwmin * one_eps;  // round up
    iwork[0] = liwmin;

    magma_queue_destroy( stream );
    magma_free( dwork );

    return *info;
} /* magma_ssyevd_gpu */
Ejemplo n.º 3
0
extern "C" magma_int_t
magma_ssyevdx_2stage(char jobz, char range, char uplo,
                     magma_int_t n,
                     float *a, magma_int_t lda,
                     float vl, float vu, magma_int_t il, magma_int_t iu,
                     magma_int_t *m, float *w,
                     float *work, magma_int_t lwork,
                     magma_int_t *iwork, magma_int_t liwork,
                     magma_int_t *info)
{
/*  -- MAGMA (version 1.4.1) --
       Univ. of Tennessee, Knoxville
       Univ. of California, Berkeley
       Univ. of Colorado, Denver
       December 2013

    Purpose
    =======
    ZHEEVD_2STAGE computes all eigenvalues and, optionally, eigenvectors of a
    complex Hermitian matrix A. It uses a two-stage algorithm for the tridiagonalization.
    If eigenvectors are desired, it uses a divide and conquer algorithm.

    The divide and conquer algorithm makes very mild assumptions about
    floating point arithmetic. It will work on machines with a guard
    digit in add/subtract, or on those binary machines without guard
    digits which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or
    Cray-2. It could conceivably fail on hexadecimal or decimal machines
    without guard digits, but we know of none.

    Arguments
    =========
    JOBZ    (input) CHARACTER*1
            = 'N':  Compute eigenvalues only;
            = 'V':  Compute eigenvalues and eigenvectors.

    RANGE   (input) CHARACTER*1
            = 'A': all eigenvalues will be found.
            = 'V': all eigenvalues in the half-open interval (VL,VU]
                   will be found.
            = 'I': the IL-th through IU-th eigenvalues will be found.

    UPLO    (input) CHARACTER*1
            = 'U':  Upper triangle of A is stored;
            = 'L':  Lower triangle of A is stored.

    N       (input) INTEGER
            The order of the matrix A.  N >= 0.

    A       (input/output) COMPLEX_16 array, dimension (LDA, N)
            On entry, the Hermitian matrix A.  If UPLO = 'U', the
            leading N-by-N upper triangular part of A contains the
            upper triangular part of the matrix A.  If UPLO = 'L',
            the leading N-by-N lower triangular part of A contains
            the lower triangular part of the matrix A.
            On exit, if JOBZ = 'V', then if INFO = 0, the first m columns
            of A contains the required
            orthonormal eigenvectors of the matrix A.
            If JOBZ = 'N', then on exit the lower triangle (if UPLO='L')
            or the upper triangle (if UPLO='U') of A, including the
            diagonal, is destroyed.

    LDA     (input) INTEGER
            The leading dimension of the array A.  LDA >= max(1,N).

    VL      (input) REAL
    VU      (input) REAL
            If RANGE='V', the lower and upper bounds of the interval to
            be searched for eigenvalues. VL < VU.
            Not referenced if RANGE = 'A' or 'I'.

    IL      (input) INTEGER
    IU      (input) INTEGER
            If RANGE='I', the indices (in ascending order) of the
            smallest and largest eigenvalues to be returned.
            1 <= IL <= IU <= N, if N > 0; IL = 1 and IU = 0 if N = 0.
            Not referenced if RANGE = 'A' or 'V'.

    M       (output) INTEGER
            The total number of eigenvalues found.  0 <= M <= N.
            If RANGE = 'A', M = N, and if RANGE = 'I', M = IU-IL+1.

    W       (output) REAL array, dimension (N)
            If INFO = 0, the required m eigenvalues in ascending order.

    WORK    (workspace/output) COMPLEX_16 array, dimension (MAX(1,LWORK))
            On exit, if INFO = 0, WORK(1) returns the optimal LWORK.

    LWORK   (input) INTEGER
            The length of the array WORK.
            If N <= 1,                LWORK >= 1.
            If JOBZ  = 'N' and N > 1, LWORK >= LQ2 + N * (NB + 2).
            If JOBZ  = 'V' and N > 1, LWORK >= LQ2 + 1 + 6*N + 2*N**2.
                                      where LQ2 is the size needed to store
                                      the Q2 matrix and is returned by
                                      MAGMA_BULGE_GET_LQ2.

            If LWORK = -1, then a workspace query is assumed; the routine
            only calculates the optimal sizes of the WORK, RWORK and
            IWORK arrays, returns these values as the first entries of
            the WORK, RWORK and IWORK arrays, and no error message
            related to LWORK or LRWORK or LIWORK is issued by XERBLA.

    IWORK   (workspace/output) INTEGER array, dimension (MAX(1,LIWORK))
            On exit, if INFO = 0, IWORK(1) returns the optimal LIWORK.

    LIWORK  (input) INTEGER
            The dimension of the array IWORK.
            If N <= 1,                LIWORK >= 1.
            If JOBZ  = 'N' and N > 1, LIWORK >= 1.
            If JOBZ  = 'V' and N > 1, LIWORK >= 3 + 5*N.

            If LIWORK = -1, then a workspace query is assumed; the
            routine only calculates the optimal sizes of the WORK, RWORK
            and IWORK arrays, returns these values as the first entries
            of the WORK, RWORK and IWORK arrays, and no error message
            related to LWORK or LRWORK or LIWORK is issued by XERBLA.

    INFO    (output) INTEGER
            = 0:  successful exit
            < 0:  if INFO = -i, the i-th argument had an illegal value
            > 0:  if INFO = i and JOBZ = 'N', then the algorithm failed
                  to converge; i off-diagonal elements of an intermediate
                  tridiagonal form did not converge to zero;
                  if INFO = i and JOBZ = 'V', then the algorithm failed
                  to compute an eigenvalue while working on the submatrix
                  lying in rows and columns INFO/(N+1) through
                  mod(INFO,N+1).

    Further Details
    ===============
    Based on contributions by
       Jeff Rutter, Computer Science Division, University of California
       at Berkeley, USA

    Modified description of INFO. Sven, 16 Feb 05.
    =====================================================================   */

    char uplo_[2] = {uplo, 0};
    char jobz_[2] = {jobz, 0};
    char range_[2] = {range, 0};
    float d_one  = 1.;
    magma_int_t ione = 1;
    magma_int_t izero = 0;

    float d__1;

    float eps;
    float anrm;
    magma_int_t imax;
    float rmin, rmax;
    float sigma;
    magma_int_t lwmin, liwmin;
    magma_int_t lower;
    magma_int_t wantz;
    magma_int_t iscale;
    float safmin;
    float bignum;
    float smlnum;
    magma_int_t lquery;
    magma_int_t alleig, valeig, indeig;

    float* dwork;

    /* determine the number of threads */
    magma_int_t threads = magma_get_numthreads();
    magma_setlapack_numthreads(threads);

    wantz = lapackf77_lsame(jobz_, MagmaVecStr);
    lower = lapackf77_lsame(uplo_, MagmaLowerStr);

    alleig = lapackf77_lsame( range_, "A" );
    valeig = lapackf77_lsame( range_, "V" );
    indeig = lapackf77_lsame( range_, "I" );

    lquery = lwork == -1 || liwork == -1;

    *info = 0;
    if (! (wantz || lapackf77_lsame(jobz_, MagmaNoVecStr))) {
        *info = -1;
    } else if (! (alleig || valeig || indeig)) {
        *info = -2;
    } else if (! (lower || lapackf77_lsame(uplo_, MagmaUpperStr))) {
        *info = -3;
    } else if (n < 0) {
        *info = -4;
    } else if (lda < max(1,n)) {
        *info = -6;
    } else {
        if (valeig) {
            if (n > 0 && vu <= vl) {
                *info = -8;
            }
        } else if (indeig) {
            if (il < 1 || il > max(1,n)) {
                *info = -9;
            } else if (iu < min(n,il) || iu > n) {
                *info = -10;
            }
        }
    }

    magma_int_t nb = magma_get_sbulge_nb(n, threads);
    magma_int_t Vblksiz = magma_sbulge_get_Vblksiz(n, nb, threads);

    magma_int_t ldt = Vblksiz;
    magma_int_t ldv = nb + Vblksiz;
    magma_int_t blkcnt = magma_bulge_get_blkcnt(n, nb, Vblksiz);
    magma_int_t lq2 = magma_sbulge_get_lq2(n, threads);

    if (wantz) {
        lwmin = lq2 + 1 + 6 * n + 2 * n * n;
        liwmin = 5 * n + 3;
    } else {
        lwmin = lq2 + n * (nb + 1);
        liwmin = 1;
    }

    work[0] = lwmin * (1. + lapackf77_slamch("Epsilon"));
    iwork[0] = liwmin;

    if ((lwork < lwmin) && !lquery) {
        *info = -14;
    } else if ((liwork < liwmin) && ! lquery) {
        *info = -16;
    }

    if (*info != 0) {
        magma_xerbla( __func__, -(*info) );
        return *info;
    }
    else if (lquery) {
        return *info;
    }
    /* Quick return if possible */
    if (n == 0) {
        return *info;
    }

    if (n == 1) {
        w[0] = a[0];
        if (wantz) {
            a[0] = MAGMA_S_ONE;
        }
        return *info;
    }

#ifdef ENABLE_TIMER
    printf("using %d threads\n", threads);
#endif
    /* Check if matrix is very small then just call LAPACK on CPU, no need for GPU */
    magma_int_t ntiles = n/nb;
    if( ( ntiles < 2 ) || ( n <= 128 ) ){
        #ifdef ENABLE_DEBUG
        printf("--------------------------------------------------------------\n");
        printf("  warning matrix too small N=%d NB=%d, calling lapack on CPU  \n", (int) n, (int ) nb);
        printf("--------------------------------------------------------------\n");
        #endif
        lapackf77_ssyevd(jobz_, uplo_, &n, 
                        a, &lda, w, 
                        work, &lwork, 
                        iwork, &liwork, 
                        info);
        *m = n; 
        return *info;
    }

    /* Get machine constants. */
    safmin = lapackf77_slamch("Safe minimum");
    eps = lapackf77_slamch("Precision");
    smlnum = safmin / eps;
    bignum = 1. / smlnum;
    rmin = magma_ssqrt(smlnum);
    rmax = magma_ssqrt(bignum);

    /* Scale matrix to allowable range, if necessary. */
    anrm = lapackf77_slansy("M", uplo_, &n, a, &lda, work);
    iscale = 0;
    if (anrm > 0. && anrm < rmin) {
        iscale = 1;
        sigma = rmin / anrm;
    } else if (anrm > rmax) {
        iscale = 1;
        sigma = rmax / anrm;
    }
    if (iscale == 1) {
        lapackf77_slascl(uplo_, &izero, &izero, &d_one, &sigma, &n, &n, a,
                         &lda, info);
    }

    magma_int_t inde    = 0;
    magma_int_t indT2   = inde + n;
    magma_int_t indTAU2 = indT2  + blkcnt*ldt*Vblksiz;
    magma_int_t indV2   = indTAU2+ blkcnt*Vblksiz;
    magma_int_t indtau1 = indV2  + blkcnt*ldv*Vblksiz;
    magma_int_t indwrk  = indtau1+ n;
    magma_int_t indwk2  = indwrk + n * n;

    magma_int_t llwork = lwork - indwrk;
    magma_int_t llwrk2 = lwork - indwk2;

#ifdef ENABLE_TIMER
    magma_timestr_t start, st1, st2, end;
    start = get_current_time();
#endif

    float *dT1;

    if (MAGMA_SUCCESS != magma_smalloc( &dT1, n*nb)) {
        *info = MAGMA_ERR_DEVICE_ALLOC;
        return *info;
    }

    magma_ssytrd_sy2sb(uplo, n, nb, a, lda, &work[indtau1], &work[indwrk], llwork, dT1, threads, info);

#ifdef ENABLE_TIMER
    st1 = get_current_time();
    printf("  time ssytrd_sy2sb = %6.2f\n" , GetTimerValue(start,st1)/1000.);
#endif

    /* copy the input matrix into WORK(INDWRK) with band storage */
    /* PAY ATTENTION THAT work[indwrk] should be able to be of size lda2*n which it should be checked in any future modification of lwork.*/
    magma_int_t lda2 = 2*nb; //nb+1+(nb-1);
    float* A2 = &work[indwrk];
    memset(A2 , 0, n*lda2*sizeof(float));

    for (magma_int_t j = 0; j < n-nb; j++)
    {
        cblas_scopy(nb+1, &a[j*(lda+1)], 1, &A2[j*lda2], 1);
        memset(&a[j*(lda+1)], 0, (nb+1)*sizeof(float));
        a[nb + j*(lda+1)] = d_one;
    }
    for (magma_int_t j = 0; j < nb; j++)
    {
        cblas_scopy(nb-j, &a[(j+n-nb)*(lda+1)], 1, &A2[(j+n-nb)*lda2], 1);
        memset(&a[(j+n-nb)*(lda+1)], 0, (nb-j)*sizeof(float));
    }

#ifdef ENABLE_TIMER
    st2 = get_current_time();
    printf("  time ssytrd_convert = %6.2f\n" , GetTimerValue(st1,st2)/1000.);
#endif

    magma_ssytrd_sb2st(threads, uplo, n, nb, Vblksiz, A2, lda2, w, &work[inde], &work[indV2], ldv, &work[indTAU2], wantz, &work[indT2], ldt);

#ifdef ENABLE_TIMER
    end = get_current_time();
    printf("  time ssytrd_sy2st = %6.2f\n" , GetTimerValue(st2,end)/1000.);
    printf("  time ssytrd = %6.2f\n", GetTimerValue(start,end)/1000.);
#endif

    /* For eigenvalues only, call SSTERF.  For eigenvectors, first call
     ZSTEDC to generate the eigenvector matrix, WORK(INDWRK), of the
     tridiagonal matrix, then call ZUNMTR to multiply it to the Householder
     transformations represented as Householder vectors in A. */
    if (! wantz) {
#ifdef ENABLE_TIMER
        start = get_current_time();
#endif

        lapackf77_ssterf(&n, w, &work[inde], info);
        magma_smove_eig(range, n, w, &il, &iu, vl, vu, m);

#ifdef ENABLE_TIMER
        end = get_current_time();
        printf("  time sstedc = %6.2f\n", GetTimerValue(start,end)/1000.);
#endif
    } else {

#ifdef ENABLE_TIMER
        start = get_current_time();
#endif

        if (MAGMA_SUCCESS != magma_smalloc( &dwork, 3*n*(n/2 + 1) )) {
            *info = MAGMA_ERR_DEVICE_ALLOC;
            return *info;
        }

        magma_sstedx(range, n, vl, vu, il, iu, w, &work[inde],
                     &work[indwrk], n, &work[indwk2],
                     llwrk2, iwork, liwork, dwork, info);

        magma_free( dwork );

#ifdef ENABLE_TIMER
        end = get_current_time();
        printf("  time sstedx = %6.2f\n", GetTimerValue(start,end)/1000.);
        start = get_current_time();
#endif
        float *dZ;
        magma_int_t lddz = n;

        float *da;
        magma_int_t ldda = n;

        magma_smove_eig(range, n, w, &il, &iu, vl, vu, m);

        if (MAGMA_SUCCESS != magma_smalloc( &dZ, *m*lddz)) {
            *info = MAGMA_ERR_DEVICE_ALLOC;
            return *info;
        }
        if (MAGMA_SUCCESS != magma_smalloc( &da, n*ldda )) {
            *info = MAGMA_ERR_DEVICE_ALLOC;
            return *info;
        }

        magma_sbulge_back(threads, uplo, n, nb, *m, Vblksiz, &work[indwrk + n * (il-1)], n, dZ, lddz,
                          &work[indV2], ldv, &work[indTAU2], &work[indT2], ldt, info);

#ifdef ENABLE_TIMER
        st1 = get_current_time();

        printf("  time sbulge_back = %6.2f\n" , GetTimerValue(start,st1)/1000.);
#endif

        magma_ssetmatrix( n, n, a, lda, da, ldda );

        magma_sormqr_gpu_2stages(MagmaLeft, MagmaNoTrans, n-nb, *m, n-nb, da+nb, ldda,
                                 dZ+nb, n, dT1, nb, info);

        magma_sgetmatrix( n, *m, dZ, lddz, a, lda );
        magma_free(dT1);
        magma_free(dZ);
        magma_free(da);

#ifdef ENABLE_TIMER
        end = get_current_time();
        printf("  time sormqr + copy = %6.2f\n", GetTimerValue(st1,end)/1000.);

        printf("  time eigenvectors backtransf. = %6.2f\n" , GetTimerValue(start,end)/1000.);
#endif

    }

    /* If matrix was scaled, then rescale eigenvalues appropriately. */
    if (iscale == 1) {
        if (*info == 0) {
            imax = n;
        } else {
            imax = *info - 1;
        }
        d__1 = 1. / sigma;
        blasf77_sscal(&imax, &d__1, w, &ione);
    }

    work[0] = lwmin * (1. + lapackf77_slamch("Epsilon"));
    iwork[0] = liwmin;

    return *info;
} /* magma_zheevdx_2stage */
Ejemplo n.º 4
0
/**
    Purpose
    -------
    SSYEVD_GPU computes all eigenvalues and, optionally, eigenvectors of
    a real symmetric matrix A.  If eigenvectors are desired, it uses a
    divide and conquer algorithm.

    The divide and conquer algorithm makes very mild assumptions about
    floating point arithmetic. It will work on machines with a guard
    digit in add/subtract, or on those binary machines without guard
    digits which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or
    Cray-2. It could conceivably fail on hexadecimal or decimal machines
    without guard digits, but we know of none.

    Arguments
    ---------
    @param[in]
    jobz    magma_vec_t
      -     = MagmaNoVec:  Compute eigenvalues only;
      -     = MagmaVec:    Compute eigenvalues and eigenvectors.

    @param[in]
    uplo    magma_uplo_t
      -     = MagmaUpper:  Upper triangle of A is stored;
      -     = MagmaLower:  Lower triangle of A is stored.

    @param[in]
    n       INTEGER
            The order of the matrix A.  N >= 0.

    @param[in,out]
    dA      REAL array on the GPU,
            dimension (LDDA, N).
            On entry, the symmetric matrix A.  If UPLO = MagmaUpper, the
            leading N-by-N upper triangular part of A contains the
            upper triangular part of the matrix A.  If UPLO = MagmaLower,
            the leading N-by-N lower triangular part of A contains
            the lower triangular part of the matrix A.
            On exit, if JOBZ = MagmaVec, then if INFO = 0, A contains the
            orthonormal eigenvectors of the matrix A.
            If JOBZ = MagmaNoVec, then on exit the lower triangle (if UPLO=MagmaLower)
            or the upper triangle (if UPLO=MagmaUpper) of A, including the
            diagonal, is destroyed.

    @param[in]
    ldda    INTEGER
            The leading dimension of the array DA.  LDDA >= max(1,N).

    @param[out]
    w       REAL array, dimension (N)
            If INFO = 0, the eigenvalues in ascending order.

    @param
    wA      (workspace) REAL array, dimension (LDWA, N)

    @param[in]
    ldwa    INTEGER
            The leading dimension of the array wA.  LDWA >= max(1,N).

    @param[out]
    work    (workspace) REAL array, dimension (MAX(1,LWORK))
            On exit, if INFO = 0, WORK[0] returns the optimal LWORK.

    @param[in]
    lwork   INTEGER
            The length of the array WORK.
            If N <= 1,                      LWORK >= 1.
            If JOBZ = MagmaNoVec and N > 1, LWORK >= 2*N + N*NB.
            If JOBZ = MagmaVec   and N > 1, LWORK >= max( 2*N + N*NB, 1 + 6*N + 2*N**2 ).
            NB can be obtained through magma_get_ssytrd_nb(N).
    \n
            If LWORK = -1, then a workspace query is assumed; the routine
            only calculates the optimal sizes of the WORK and IWORK
            arrays, returns these values as the first entries of the WORK
            and IWORK arrays, and no error message related to LWORK or
            LIWORK is issued by XERBLA.

    @param[out]
    iwork   (workspace) INTEGER array, dimension (MAX(1,LIWORK))
            On exit, if INFO = 0, IWORK[0] returns the optimal LIWORK.

    @param[in]
    liwork  INTEGER
            The dimension of the array IWORK.
            If N <= 1,                       LIWORK >= 1.
            If JOBZ = MagmaNoVec and N > 1, LIWORK >= 1.
            If JOBZ  = MagmaVec   and N > 1, LIWORK >= 3 + 5*N.
    \n
            If LIWORK = -1, then a workspace query is assumed; the
            routine only calculates the optimal sizes of the WORK and
            IWORK arrays, returns these values as the first entries of
            the WORK and IWORK arrays, and no error message related to
            LWORK or LIWORK is issued by XERBLA.

    @param[out]
    info    INTEGER
      -     = 0:  successful exit
      -     < 0:  if INFO = -i, the i-th argument had an illegal value
      -     > 0:  if INFO = i and JOBZ = MagmaNoVec, then the algorithm failed
                  to converge; i off-diagonal elements of an intermediate
                  tridiagonal form did not converge to zero;
                  if INFO = i and JOBZ = MagmaVec, then the algorithm failed
                  to compute an eigenvalue while working on the submatrix
                  lying in rows and columns INFO/(N+1) through
                  mod(INFO,N+1).

    Further Details
    ---------------
    Based on contributions by
       Jeff Rutter, Computer Science Division, University of California
       at Berkeley, USA

    Modified description of INFO. Sven, 16 Feb 05.

    @ingroup magma_ssyev_driver
    ********************************************************************/
extern "C" magma_int_t
magma_ssyevd_gpu(
    magma_vec_t jobz, magma_uplo_t uplo,
    magma_int_t n,
    magmaFloat_ptr dA, magma_int_t ldda,
    float *w,
    float *wA,  magma_int_t ldwa,
    float *work, magma_int_t lwork,
    #ifdef COMPLEX
    float *rwork, magma_int_t lrwork,
    #endif
    magma_int_t *iwork, magma_int_t liwork,
    magma_int_t *info)
{
    magma_int_t ione = 1;

    float d__1;

    float eps;
    magma_int_t inde;
    float anrm;
    float rmin, rmax;
    float sigma;
    magma_int_t iinfo, lwmin;
    magma_int_t lower;
    magma_int_t wantz;
    magma_int_t indwk2, llwrk2;
    magma_int_t iscale;
    float safmin;
    float bignum;
    magma_int_t indtau;
    magma_int_t indwrk, liwmin;
    magma_int_t llwork;
    float smlnum;
    magma_int_t lquery;

    magmaFloat_ptr dwork;
    magma_int_t lddc = ldda;

    wantz = (jobz == MagmaVec);
    lower = (uplo == MagmaLower);
    lquery = (lwork == -1 || liwork == -1);

    *info = 0;
    if (! (wantz || (jobz == MagmaNoVec))) {
        *info = -1;
    } else if (! (lower || (uplo == MagmaUpper))) {
        *info = -2;
    } else if (n < 0) {
        *info = -3;
    } else if (ldda < max(1,n)) {
        *info = -5;
    }

    magma_int_t nb = magma_get_ssytrd_nb( n );
    if ( n <= 1 ) {
        lwmin  = 1;
        liwmin = 1;
    }
    else if ( wantz ) {
        lwmin  = max( 2*n + n*nb, 1 + 6*n + 2*n*n );
        liwmin = 3 + 5*n;
    }
    else {
        lwmin  = 2*n + n*nb;
        liwmin = 1;
    }
    
    work[0]  = magma_smake_lwork( lwmin );
    iwork[0] = liwmin;

    if ((lwork < lwmin) && !lquery) {
        *info = -10;
    } else if ((liwork < liwmin) && ! lquery) {
        *info = -12;
    }

    if (*info != 0) {
        magma_xerbla( __func__, -(*info) );
        return *info;
    }
    else if (lquery) {
        return *info;
    }

    magma_queue_t queue;
    magma_device_t cdev;
    magma_getdevice( &cdev );
    magma_queue_create( cdev, &queue );

    /* If matrix is very small, then just call LAPACK on CPU, no need for GPU */
    if (n <= 128) {
        magma_int_t lda = n;
        float *A;
        magma_smalloc_cpu( &A, lda*n );
        magma_sgetmatrix( n, n, dA, ldda, A, lda, queue );
        lapackf77_ssyevd( lapack_vec_const(jobz), lapack_uplo_const(uplo),
                          &n, A, &lda,
                          w, work, &lwork,
                          iwork, &liwork, info );
        magma_ssetmatrix( n, n, A, lda, dA, ldda, queue );
        magma_free_cpu( A );
        magma_queue_destroy( queue );
        return *info;
    }

    // ssytrd2_gpu requires ldda*ceildiv(n,64) + 2*ldda*nb
    // sormtr_gpu  requires lddc*n
    // slansy      requires n
    magma_int_t ldwork = max( ldda*magma_ceildiv(n,64) + 2*ldda*nb, lddc*n );
    ldwork = max( ldwork, n );
    if ( wantz ) {
        // sstedx requires 3n^2/2
        ldwork = max( ldwork, 3*n*(n/2 + 1) );
    }
    if (MAGMA_SUCCESS != magma_smalloc( &dwork, ldwork )) {
        *info = MAGMA_ERR_DEVICE_ALLOC;
        return *info;
    }

    /* Get machine constants. */
    safmin = lapackf77_slamch("Safe minimum");
    eps    = lapackf77_slamch("Precision");
    smlnum = safmin / eps;
    bignum = 1. / smlnum;
    rmin = magma_ssqrt( smlnum );
    rmax = magma_ssqrt( bignum );

    /* Scale matrix to allowable range, if necessary. */
    anrm = magmablas_slansy( MagmaMaxNorm, uplo, n, dA, ldda, dwork, ldwork, queue );
    iscale = 0;
    sigma  = 1;
    if (anrm > 0. && anrm < rmin) {
        iscale = 1;
        sigma = rmin / anrm;
    } else if (anrm > rmax) {
        iscale = 1;
        sigma = rmax / anrm;
    }
    if (iscale == 1) {
        magmablas_slascl( uplo, 0, 0, 1., sigma, n, n, dA, ldda, queue, info );
    }

    /* Call SSYTRD to reduce symmetric matrix to tridiagonal form. */
    // ssytrd work: e (n) + tau (n) + llwork (n*nb)  ==>  2n + n*nb
    // sstedx work: e (n) + tau (n) + z (n*n) + llwrk2 (1 + 4*n + n^2)  ==>  1 + 6n + 2n^2
    inde   = 0;
    indtau = inde   + n;
    indwrk = indtau + n;
    indwk2 = indwrk + n*n;
    llwork = lwork - indwrk;
    llwrk2 = lwork - indwk2;

    magma_timer_t time=0;
    timer_start( time );

#ifdef FAST_SYMV
    magma_ssytrd2_gpu( uplo, n, dA, ldda, w, &work[inde],
                       &work[indtau], wA, ldwa, &work[indwrk], llwork,
                       dwork, ldwork, &iinfo );
#else
    magma_ssytrd_gpu(  uplo, n, dA, ldda, w, &work[inde],
                       &work[indtau], wA, ldwa, &work[indwrk], llwork,
                       &iinfo );
#endif

    timer_stop( time );
    #ifdef FAST_SYMV
    timer_printf( "time ssytrd2 = %6.2f\n", time );
    #else
    timer_printf( "time ssytrd = %6.2f\n", time );
    #endif

    /* For eigenvalues only, call SSTERF.  For eigenvectors, first call
       SSTEDC to generate the eigenvector matrix, WORK(INDWRK), of the
       tridiagonal matrix, then call SORMTR to multiply it to the Householder
       transformations represented as Householder vectors in A. */
    if (! wantz) {
        lapackf77_ssterf( &n, w, &work[inde], info );
    }
    else {
        timer_start( time );

        magma_sstedx( MagmaRangeAll, n, 0., 0., 0, 0, w, &work[inde],
                      &work[indwrk], n, &work[indwk2],
                      llwrk2, iwork, liwork, dwork, info );

        timer_stop( time );
        timer_printf( "time sstedx = %6.2f\n", time );
        timer_start( time );

        magma_ssetmatrix( n, n, &work[indwrk], n, dwork, lddc, queue );

        magma_sormtr_gpu( MagmaLeft, uplo, MagmaNoTrans, n, n, dA, ldda, &work[indtau],
                          dwork, lddc, wA, ldwa, &iinfo );

        magma_scopymatrix( n, n, dwork, lddc, dA, ldda, queue );

        timer_stop( time );
        timer_printf( "time sormtr + copy = %6.2f\n", time );
    }

    /* If matrix was scaled, then rescale eigenvalues appropriately. */
    if (iscale == 1) {
        d__1 = 1. / sigma;
        blasf77_sscal( &n, &d__1, w, &ione );
    }

    work[0]  = magma_smake_lwork( lwmin );
    iwork[0] = liwmin;

    magma_queue_destroy( queue );
    magma_free( dwork );

    return *info;
} /* magma_ssyevd_gpu */
Ejemplo n.º 5
0
/* ////////////////////////////////////////////////////////////////////////////
   -- Testing ssyevd
*/
int main( int argc, char** argv)
{
    TESTING_INIT();

    real_Double_t   gpu_time, cpu_time;
    float *h_A, *h_R, *h_work;
    float *w1, *w2;
    magma_int_t *iwork;
    magma_int_t N, n2, info, lwork, liwork, lda, aux_iwork[1];
    magma_int_t izero    = 0;
    magma_int_t ione     = 1;
    magma_int_t ISEED[4] = {0,0,0,1};
    float result[3], eps, aux_work[1];
    eps = lapackf77_slamch( "E" );
    magma_int_t status = 0;

    magma_opts opts;
    parse_opts( argc, argv, &opts );

    float tol    = opts.tolerance * lapackf77_slamch("E");
    float tolulp = opts.tolerance * lapackf77_slamch("P");
    
    if ( opts.check && opts.jobz == MagmaNoVec ) {
        fprintf( stderr, "checking results requires vectors; setting jobz=V (option -JV)\n" );
        opts.jobz = MagmaVec;
    }
    
    printf("using: jobz = %s, uplo = %s\n",
           lapack_vec_const(opts.jobz), lapack_uplo_const(opts.uplo));

    printf("    N   CPU Time (sec)   GPU Time (sec)\n");
    printf("=======================================\n");
    for( int itest = 0; itest < opts.ntest; ++itest ) {
        for( int iter = 0; iter < opts.niter; ++iter ) {
            N = opts.nsize[itest];
            n2  = N*N;
            lda = N;
            
            // query for workspace sizes
            magma_ssyevd( opts.jobz, opts.uplo,
                          N, NULL, lda, NULL,
                          aux_work,  -1,
                          aux_iwork, -1,
                          &info );
            lwork  = (magma_int_t) aux_work[0];
            liwork = aux_iwork[0];
            
            /* Allocate host memory for the matrix */
            TESTING_MALLOC_CPU( h_A,    float, N*lda );
            TESTING_MALLOC_CPU( w1,     float, N     );
            TESTING_MALLOC_CPU( w2,     float, N     );
            TESTING_MALLOC_CPU( iwork,  magma_int_t, liwork );
            
            TESTING_MALLOC_PIN( h_R,    float, N*lda  );
            TESTING_MALLOC_PIN( h_work, float, lwork  );
            
            /* Initialize the matrix */
            lapackf77_slarnv( &ione, ISEED, &n2, h_A );
            lapackf77_slacpy( MagmaUpperLowerStr, &N, &N, h_A, &lda, h_R, &lda );
            
            /* warm up run */
            if ( opts.warmup ) {
                magma_ssyevd( opts.jobz, opts.uplo,
                              N, h_R, lda, w1,
                              h_work, lwork,
                              iwork, liwork,
                              &info );
                if (info != 0)
                    printf("magma_ssyevd returned error %d: %s.\n",
                           (int) info, magma_strerror( info ));
                lapackf77_slacpy( MagmaUpperLowerStr, &N, &N, h_A, &lda, h_R, &lda );
            }
            
            /* ====================================================================
               Performs operation using MAGMA
               =================================================================== */
            gpu_time = magma_wtime();
            magma_ssyevd( opts.jobz, opts.uplo,
                          N, h_R, lda, w1,
                          h_work, lwork,
                          iwork, liwork,
                          &info );
            gpu_time = magma_wtime() - gpu_time;
            if (info != 0)
                printf("magma_ssyevd returned error %d: %s.\n",
                       (int) info, magma_strerror( info ));
            
            if ( opts.check ) {
                /* =====================================================================
                   Check the results following the LAPACK's [zcds]drvst routine.
                   A is factored as A = U S U' and the following 3 tests computed:
                   (1)    | A - U S U' | / ( |A| N )
                   (2)    | I - U'U | / ( N )
                   (3)    | S(with U) - S(w/o U) | / | S |
                   =================================================================== */
                float temp1, temp2;
                
                // tau=NULL is unused since itype=1
                lapackf77_ssyt21( &ione, lapack_uplo_const(opts.uplo), &N, &izero,
                                  h_A, &lda,
                                  w1, h_work,
                                  h_R, &lda,
                                  h_R, &lda,
                                  NULL, h_work, &result[0] );
                
                lapackf77_slacpy( MagmaUpperLowerStr, &N, &N, h_A, &lda, h_R, &lda );
                magma_ssyevd( MagmaNoVec, opts.uplo,
                              N, h_R, lda, w2,
                              h_work, lwork,
                              iwork, liwork,
                              &info );
                if (info != 0)
                    printf("magma_ssyevd returned error %d: %s.\n",
                           (int) info, magma_strerror( info ));
                
                temp1 = temp2 = 0;
                for( int j=0; j<N; j++ ) {
                    temp1 = max(temp1, fabsf(w1[j]));
                    temp1 = max(temp1, fabsf(w2[j]));
                    temp2 = max(temp2, fabsf(w1[j]-w2[j]));
                }
                result[2] = temp2 / (((float)N)*temp1);
            }
            
            /* =====================================================================
               Performs operation using LAPACK
               =================================================================== */
            if ( opts.lapack ) {
                cpu_time = magma_wtime();
                lapackf77_ssyevd( lapack_vec_const(opts.jobz), lapack_uplo_const(opts.uplo),
                                  &N, h_A, &lda, w2,
                                  h_work, &lwork,
                                  iwork, &liwork,
                                  &info );
                cpu_time = magma_wtime() - cpu_time;
                if (info != 0)
                    printf("lapackf77_ssyevd returned error %d: %s.\n",
                           (int) info, magma_strerror( info ));
                
                printf("%5d   %7.2f          %7.2f\n",
                       (int) N, cpu_time, gpu_time);
            }
            else {
                printf("%5d     ---            %7.2f\n",
                       (int) N, gpu_time);
            }
            
            /* =====================================================================
               Print execution time
               =================================================================== */
            if ( opts.check ) {
                printf("Testing the factorization A = U S U' for correctness:\n");
                printf("(1)    | A - U S U' | / (|A| N)     = %8.2e   %s\n",   result[0]*eps, (result[0]*eps < tol ? "ok" : "failed") );
                printf("(2)    | I -   U'U  | /  N          = %8.2e   %s\n",   result[1]*eps, (result[1]*eps < tol ? "ok" : "failed") );
                printf("(3)    | S(w/ U) - S(w/o U) | / |S| = %8.2e   %s\n\n", result[2]    , (result[2]  < tolulp ? "ok" : "failed") );
                status += ! (result[0]*eps < tol && result[1]*eps < tol && result[2] < tolulp);
            }
            
            TESTING_FREE_CPU( h_A   );
            TESTING_FREE_CPU( w1    );
            TESTING_FREE_CPU( w2    );
            TESTING_FREE_CPU( iwork );
            
            TESTING_FREE_PIN( h_R    );
            TESTING_FREE_PIN( h_work );
            fflush( stdout );
        }
        if ( opts.niter > 1 ) {
            printf( "\n" );
        }
    }
    
    TESTING_FINALIZE();
    return status;
}
Ejemplo n.º 6
0
extern "C" magma_int_t
magma_ssyevd_gpu(char jobz, char uplo,
                 magma_int_t n,
                 float *da, magma_int_t ldda,
                 float *w,
                 float *wa,  magma_int_t ldwa,
                 float *work, magma_int_t lwork,
                 magma_int_t *iwork, magma_int_t liwork,
                 magma_int_t *info)
{
/*  -- MAGMA (version 1.4.0) --
       Univ. of Tennessee, Knoxville
       Univ. of California, Berkeley
       Univ. of Colorado, Denver
       August 2013

    Purpose
    =======
    SSYEVD_GPU computes all eigenvalues and, optionally, eigenvectors of
    a real symmetric matrix A.  If eigenvectors are desired, it uses a
    divide and conquer algorithm.

    The divide and conquer algorithm makes very mild assumptions about
    floating point arithmetic. It will work on machines with a guard
    digit in add/subtract, or on those binary machines without guard
    digits which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or
    Cray-2. It could conceivably fail on hexadecimal or decimal machines
    without guard digits, but we know of none.

    Arguments
    =========
    JOBZ    (input) CHARACTER*1
            = 'N':  Compute eigenvalues only;
            = 'V':  Compute eigenvalues and eigenvectors.

    UPLO    (input) CHARACTER*1
            = 'U':  Upper triangle of A is stored;
            = 'L':  Lower triangle of A is stored.

    N       (input) INTEGER
            The order of the matrix A.  N >= 0.

    DA      (device input/output) REAL array on the GPU,
            dimension (LDDA, N).
            On entry, the symmetric matrix A.  If UPLO = 'U', the
            leading N-by-N upper triangular part of A contains the
            upper triangular part of the matrix A.  If UPLO = 'L',
            the leading N-by-N lower triangular part of A contains
            the lower triangular part of the matrix A.
            On exit, if JOBZ = 'V', then if INFO = 0, A contains the
            orthonormal eigenvectors of the matrix A.
            If JOBZ = 'N', then on exit the lower triangle (if UPLO='L')
            or the upper triangle (if UPLO='U') of A, including the
            diagonal, is destroyed.

    LDDA    (input) INTEGER
            The leading dimension of the array DA.  LDDA >= max(1,N).

    W       (output) DOUBLE PRECISION array, dimension (N)
            If INFO = 0, the eigenvalues in ascending order.

    WA      (workspace) DOUBLE PRECISION array, dimension (LDWA, N)

    LDWA    (input) INTEGER
            The leading dimension of the array WA.  LDWA >= max(1,N).

    WORK    (workspace/output) REAL array, dimension (MAX(1,LWORK))
            On exit, if INFO = 0, WORK[0] returns the optimal LWORK.

    LWORK   (input) INTEGER
            The length of the array WORK.
            If N <= 1,                LWORK >= 1.
            If JOBZ  = 'N' and N > 1, LWORK >= 2*N + N*NB.
            If JOBZ  = 'V' and N > 1, LWORK >= max( 2*N + N*NB, 1 + 6*N + 2*N**2 ).
            NB can be obtained through magma_get_ssytrd_nb(N).

            If LWORK = -1, then a workspace query is assumed; the routine
            only calculates the optimal sizes of the WORK and IWORK
            arrays, returns these values as the first entries of the WORK
            and IWORK arrays, and no error message related to LWORK or
            LIWORK is issued by XERBLA.

    IWORK   (workspace/output) INTEGER array, dimension (MAX(1,LIWORK))
            On exit, if INFO = 0, IWORK[0] returns the optimal LIWORK.

    LIWORK  (input) INTEGER
            The dimension of the array IWORK.
            If N <= 1,                LIWORK >= 1.
            If JOBZ  = 'N' and N > 1, LIWORK >= 1.
            If JOBZ  = 'V' and N > 1, LIWORK >= 3 + 5*N.

            If LIWORK = -1, then a workspace query is assumed; the
            routine only calculates the optimal sizes of the WORK and
            IWORK arrays, returns these values as the first entries of
            the WORK and IWORK arrays, and no error message related to
            LWORK or LIWORK is issued by XERBLA.

    INFO    (output) INTEGER
            = 0:  successful exit
            < 0:  if INFO = -i, the i-th argument had an illegal value
            > 0:  if INFO = i and JOBZ = 'N', then the algorithm failed
                  to converge; i off-diagonal elements of an intermediate
                  tridiagonal form did not converge to zero;
                  if INFO = i and JOBZ = 'V', then the algorithm failed
                  to compute an eigenvalue while working on the submatrix
                  lying in rows and columns INFO/(N+1) through
                  mod(INFO,N+1).

    Further Details
    ===============
    Based on contributions by
       Jeff Rutter, Computer Science Division, University of California
       at Berkeley, USA

    Modified description of INFO. Sven, 16 Feb 05.
    =====================================================================   */

    char uplo_[2] = {uplo, 0};
    char jobz_[2] = {jobz, 0};
    magma_int_t ione = 1;

    float d__1;

    float eps;
    magma_int_t inde;
    float anrm;
    float rmin, rmax;
    float sigma;
    magma_int_t iinfo, lwmin;
    magma_int_t lower;
    magma_int_t wantz;
    magma_int_t indwk2, llwrk2;
    magma_int_t iscale;
    float safmin;
    float bignum;
    magma_int_t indtau;
    magma_int_t indwrk, liwmin;
    magma_int_t llwork;
    float smlnum;
    magma_int_t lquery;

    float *dwork;
    magma_int_t lddc = ldda;

    wantz = lapackf77_lsame(jobz_, MagmaVecStr);
    lower = lapackf77_lsame(uplo_, MagmaLowerStr);
    lquery = lwork == -1 || liwork == -1;

    *info = 0;
    if (! (wantz || lapackf77_lsame(jobz_, MagmaNoVecStr))) {
        *info = -1;
    } else if (! (lower || lapackf77_lsame(uplo_, MagmaUpperStr))) {
        *info = -2;
    } else if (n < 0) {
        *info = -3;
    } else if (ldda < max(1,n)) {
        *info = -5;
    }

    magma_int_t nb = magma_get_ssytrd_nb( n );
    if ( n <= 1 ) {
        lwmin  = 1;
        liwmin = 1;
    }
    else if ( wantz ) {
        lwmin  = max( 2*n + n*nb, 1 + 6*n + 2*n*n );
        liwmin = 3 + 5*n;
    }
    else {
        lwmin  = 2*n + n*nb;
        liwmin = 1;
    }
    // multiply by 1+eps to ensure length gets rounded up,
    // if it cannot be exactly represented in floating point.
    work[0]  = lwmin * (1. + lapackf77_slamch("Epsilon"));
    iwork[0] = liwmin;

    if ((lwork < lwmin) && !lquery) {
        *info = -10;
    } else if ((liwork < liwmin) && ! lquery) {
        *info = -12;
    }

    if (*info != 0) {
        magma_xerbla( __func__, -(*info) );
        return *info;
    }
    else if (lquery) {
        return *info;
    }

    /* Check if matrix is very small then just call LAPACK on CPU, no need for GPU */
    if (n <= 128) {
        #ifdef ENABLE_DEBUG
        printf("--------------------------------------------------------------\n");
        printf("  warning matrix too small N=%d NB=%d, calling lapack on CPU  \n", (int) n, (int) nb);
        printf("--------------------------------------------------------------\n");
        #endif
        char jobz_[2] = {jobz, 0}, uplo_[2] = {uplo, 0};
        float *a = (float *) malloc( n * n * sizeof(float) );
        magma_sgetmatrix(n, n, da, ldda, a, n);
        lapackf77_ssyevd(jobz_, uplo_,
                         &n, a, &n,
                         w, work, &lwork,
                         iwork, &liwork, info);
        magma_ssetmatrix( n, n, a, n, da, ldda);
        free(a);
        return *info;
    }

    magma_queue_t stream;
    magma_queue_create( &stream );

    // n*lddc for ssytrd2_gpu
    // n for slansy
    magma_int_t ldwork = n*lddc;
    if ( wantz ) {
        // need 3n^2/2 for sstedx
        ldwork = max( ldwork, 3*n*(n/2 + 1));
    }

    if (MAGMA_SUCCESS != magma_smalloc( &dwork, ldwork )) {
        *info = MAGMA_ERR_DEVICE_ALLOC;
        return *info;
    }

    /* Get machine constants. */
    safmin = lapackf77_slamch("Safe minimum");
    eps    = lapackf77_slamch("Precision");
    smlnum = safmin / eps;
    bignum = 1. / smlnum;
    rmin = magma_ssqrt(smlnum);
    rmax = magma_ssqrt(bignum);

    /* Scale matrix to allowable range, if necessary. */
    anrm = magmablas_slansy('M', uplo, n, da, ldda, dwork);
    iscale = 0;
    sigma  = 1;
    if (anrm > 0. && anrm < rmin) {
        iscale = 1;
        sigma = rmin / anrm;
    } else if (anrm > rmax) {
        iscale = 1;
        sigma = rmax / anrm;
    }
    if (iscale == 1) {
        magmablas_slascl(uplo, 0, 0, 1., sigma, n, n, da, ldda, info);
    }

    /* Call SSYTRD to reduce symmetric matrix to tridiagonal form. */
    // ssytrd work: e (n) + tau (n) + llwork (n*nb)  ==>  2n + n*nb
    // sstedx work: e (n) + tau (n) + z (n*n) + llwrk2 (1 + 4*n + n^2)  ==>  1 + 6n + 2n^2
    inde   = 0;
    indtau = inde   + n;
    indwrk = indtau + n;
    indwk2 = indwrk + n*n;
    llwork = lwork - indwrk;
    llwrk2 = lwork - indwk2;

//
#ifdef ENABLE_TIMER
    magma_timestr_t start, end;
    start = get_current_time();
#endif

#ifdef FAST_SYMV
    magma_ssytrd2_gpu(uplo, n, da, ldda, w, &work[inde],
                      &work[indtau], wa, ldwa, &work[indwrk], llwork,
                      dwork, n*lddc, &iinfo);
#else
    magma_ssytrd_gpu(uplo, n, da, ldda, w, &work[inde],
                     &work[indtau], wa, ldwa, &work[indwrk], llwork,
                     &iinfo);
#endif

#ifdef ENABLE_TIMER
    end = get_current_time();
    #ifdef FAST_SYMV
    printf("time ssytrd2 = %6.2f\n", GetTimerValue(start,end)/1000.);
    #else
    printf("time ssytrd = %6.2f\n", GetTimerValue(start,end)/1000.);
    #endif
#endif

    /* For eigenvalues only, call SSTERF.  For eigenvectors, first call
       SSTEDC to generate the eigenvector matrix, WORK(INDWRK), of the
       tridiagonal matrix, then call SORMTR to multiply it to the Householder
       transformations represented as Householder vectors in A. */
    if (! wantz) {
        lapackf77_ssterf(&n, w, &work[inde], info);
    } else {

#ifdef ENABLE_TIMER
        start = get_current_time();
#endif

        magma_sstedx('A', n, 0., 0., 0, 0, w, &work[inde],
                     &work[indwrk], n, &work[indwk2],
                     llwrk2, iwork, liwork, dwork, info);

#ifdef ENABLE_TIMER
        end = get_current_time();
        printf("time sstedx = %6.2f\n", GetTimerValue(start,end)/1000.);
#endif

        magma_ssetmatrix( n, n, &work[indwrk], n, dwork, lddc );

#ifdef ENABLE_TIMER
        start = get_current_time();
#endif

        magma_sormtr_gpu(MagmaLeft, uplo, MagmaNoTrans, n, n, da, ldda, &work[indtau],
                         dwork, lddc, wa, ldwa, &iinfo);

        magma_scopymatrix( n, n, dwork, lddc, da, ldda );

#ifdef ENABLE_TIMER
        end = get_current_time();
        printf("time sormtr + copy = %6.2f\n", GetTimerValue(start,end)/1000.);
#endif
    }

    /* If matrix was scaled, then rescale eigenvalues appropriately. */
    if (iscale == 1) {
        d__1 = 1. / sigma;
        blasf77_sscal(&n, &d__1, w, &ione);
    }

    work[0]  = lwmin * (1. + lapackf77_slamch("Epsilon"));  // round up
    iwork[0] = liwmin;

    magma_queue_destroy( stream );
    magma_free( dwork );

    return *info;
} /* magma_ssyevd_gpu */
Ejemplo n.º 7
0
/* ////////////////////////////////////////////////////////////////////////////
   -- Testing ssygvdx
*/
int main( int argc, char** argv)
{

    TESTING_INIT();

    real_Double_t gpu_time;

    float *h_A, *h_R, *h_work;

#if defined(PRECISION_z) || defined(PRECISION_c)
    float *rwork;
    magma_int_t lrwork;
#endif

    /* Matrix size */
    float *w1, *w2;
    magma_int_t *iwork;
    magma_int_t N, n2, info, lwork, liwork;
    magma_int_t ione     = 1;
    magma_int_t ISEED[4] = {0,0,0,1};;
    magma_int_t info_ortho     = 0;
    magma_int_t info_solution  = 0;
    magma_int_t info_reduction = 0;

    magma_timestr_t start, end;

    magma_opts opts;
    parse_opts( argc, argv, &opts );

    magma_int_t ngpu = opts.ngpu;
    char jobz = opts.jobz;
    magma_int_t checkres = opts.check;

    char range = 'A';
    char uplo = opts.uplo;
    magma_int_t itype = opts.itype;
    float f = opts.fraction;

    if (f != 1)
        range='I';

    if ( checkres && jobz == MagmaNoVec ) {
        fprintf( stderr, "checking results requires vectors; setting jobz=V (option -JV)\n" );
        jobz = MagmaVec;
    }

    printf("using: itype = %d, jobz = %c, range = %c, uplo = %c, checkres = %d, fraction = %6.4f\n",
           (int) itype, jobz, range, uplo, (int) checkres, f);

    printf("  N     M     GPU Time(s) \n");
    printf("==========================\n");
    magma_int_t threads = magma_get_numthreads();
    for( magma_int_t i = 0; i < opts.ntest; ++i ) {
        for( magma_int_t iter = 0; iter < opts.niter; ++iter ) {
            N = opts.nsize[i];
            n2     = N*N;
#if defined(PRECISION_z) || defined(PRECISION_c)
            lwork  = magma_sbulge_get_lq2(N, threads) + 2*N + N*N;
            lrwork = 1 + 5*N +2*N*N;
#else
            lwork  = magma_sbulge_get_lq2(N, threads) + 1 + 6*N + 2*N*N;
#endif
            liwork = 3 + 5*N;

            /* Allocate host memory for the matrix */
            TESTING_MALLOC(   h_A, float, n2);
            TESTING_MALLOC(    w1, float         ,  N);
            TESTING_MALLOC(    w2, float         ,  N);
            TESTING_HOSTALLOC(h_R, float, n2);
            TESTING_HOSTALLOC(h_work, float,  lwork);
#if defined(PRECISION_z) || defined(PRECISION_c)
            TESTING_HOSTALLOC( rwork,          float, lrwork);
#endif
            TESTING_MALLOC(    iwork,     magma_int_t, liwork);


            /* Initialize the matrix */
            lapackf77_slarnv( &ione, ISEED, &n2, h_A );
            /* Make diagonal real */
            for(int i=0; i<N; i++) {
                MAGMA_S_SET2REAL( h_A[i*N+i], MAGMA_S_REAL(h_A[i*N+i]) );
            }


            magma_int_t m1 = 0;
            float vl = 0;
            float vu = 0;
            magma_int_t il = 0;
            magma_int_t iu = 0;
            if (range == 'I'){
                il = 1;
                iu = (int) (f*N);
            }

            if(opts.warmup){
                // ==================================================================
                // Warmup using MAGMA
                // ==================================================================
                lapackf77_slacpy( MagmaUpperLowerStr, &N, &N, h_A, &N, h_R, &N );
                if(ngpu==1){
                    printf("calling ssyevdx_2stage 1 GPU\n");
                    magma_ssyevdx_2stage(jobz, range, uplo, N, 
                                    h_R, N, 
                                    vl, vu, il, iu, 
                                    &m1, w1, 
                                    h_work, lwork, 
#if defined(PRECISION_z) || defined(PRECISION_c)
                                    rwork, lrwork, 
#endif         
                                    iwork, liwork, 
                                    &info);
               
                }else{
                    printf("calling ssyevdx_2stage_m %d GPU\n", (int) ngpu);
                    magma_ssyevdx_2stage_m(ngpu, jobz, range, uplo, N, 
                                    h_R, N, 
                                    vl, vu, il, iu, 
                                    &m1, w1, 
                                    h_work, lwork, 
#if defined(PRECISION_z) || defined(PRECISION_c)
                                    rwork, lrwork, 
#endif         
                                    iwork, liwork, 
                                    &info);
                }
            }


            // ===================================================================
            // Performs operation using MAGMA
            // ===================================================================
            lapackf77_slacpy( MagmaUpperLowerStr, &N, &N, h_A, &N, h_R, &N );
            start = get_current_time();
            if(ngpu==1){
                printf("calling ssyevdx_2stage 1 GPU\n");
                magma_ssyevdx_2stage(jobz, range, uplo, N, 
                                h_R, N, 
                                vl, vu, il, iu, 
                                &m1, w1, 
                                h_work, lwork, 
#if defined(PRECISION_z) || defined(PRECISION_c)
                                rwork, lrwork, 
#endif     
                                iwork, liwork, 
                                &info);
           
            }else{
                printf("calling ssyevdx_2stage_m %d GPU\n", (int) ngpu);
                magma_ssyevdx_2stage_m(ngpu, jobz, range, uplo, N, 
                                h_R, N, 
                                vl, vu, il, iu, 
                                &m1, w1, 
                                h_work, lwork, 
#if defined(PRECISION_z) || defined(PRECISION_c)
                                rwork, lrwork, 
#endif     
                                iwork, liwork, 
                                &info);
            }
            end = get_current_time();
            gpu_time = GetTimerValue(start,end)/1000.;

            if ( checkres ) {
                float eps   = lapackf77_slamch("E");
                printf("\n");
                printf("------ TESTS FOR MAGMA SSYEVD ROUTINE -------  \n");
                printf("        Size of the Matrix %d by %d\n", (int) N, (int) N);
                printf("\n");
                printf(" The matrix A is randomly generated for each test.\n");
                printf("============\n");
                printf(" The relative machine precision (eps) is %8.2e\n",eps);
                printf(" Computational tests pass if scaled residuals are less than 60.\n");
              
                /* Check the orthogonality, reduction and the eigen solutions */
                if (jobz == MagmaVec) {
                    info_ortho = check_orthogonality(N, N, h_R, N, eps);
                    info_reduction = check_reduction(uplo, N, 1, h_A, w1, N, h_R, eps);
                }
                printf("------ CALLING LAPACK SSYEVD TO COMPUTE only eigenvalue and verify elementswise -------  \n");
                lapackf77_ssyevd("N", "L", &N, 
                                h_A, &N, w2, 
                                h_work, &lwork, 
#if defined(PRECISION_z) || defined(PRECISION_c)
                                rwork, &lrwork, 
#endif     
                                iwork, &liwork, 
                                &info);
                info_solution = check_solution(N, w2, w1, eps);
              
                if ( (info_solution == 0) & (info_ortho == 0) & (info_reduction == 0) ) {
                    printf("***************************************************\n");
                    printf(" ---- TESTING SSYEVD ...................... PASSED !\n");
                    printf("***************************************************\n");
                }
                else {
                    printf("************************************************\n");
                    printf(" - TESTING SSYEVD ... FAILED !\n");
                    printf("************************************************\n");
                }
            }


            /* =====================================================================
             Print execution time
             =================================================================== */
            printf("%5d %5d     %6.2f\n",
                   (int) N, (int) m1, gpu_time);

            TESTING_FREE(       h_A);
            TESTING_FREE(        w1);
            TESTING_FREE(        w2);
#if defined(PRECISION_z) || defined(PRECISION_c)
            TESTING_HOSTFREE( rwork);
#endif
            TESTING_FREE(     iwork);
            TESTING_HOSTFREE(h_work);
            TESTING_HOSTFREE(   h_R);
        }
        if ( opts.niter > 1 ) {
            printf( "\n" );
        }
    }

    /* Shutdown */
    TESTING_FINALIZE();

    return 0;
}